Hello! Great video! It's almost what I've done. But I take a 1" thick piece of fire proof sound foam that I glued to the particle board, with a thick moving blanket folded up right on top of it all, just like you did at angles. That works unbelievable well! I do not have a dbl meter , but it is much much quieter. Plus everything just lays down flat to take up almost no space. In windy areas I use a cargo net over the whole thing, with spikes set into the ground to hold everything in place. But at home I just made a nice weather proof box, with the same fireproof sound foam.
Hey KRV! Can you possibly post photos of your matierals or a shopping list of them and how you place them to the generator... I just got my generator and your setup sounds greaT!! Thank you!!!
Nice video showing that most generator noise is not always just the exhaust. The doghouse method of noise reduction has been used by commercial home generator companies for decades with great success. Your boards deflect most of the noise into the ground where much of it is absorbed. Simple, cheap and effective. We did a lot of exhaust modifications to small engines in an attempt to quiet them and not reduce power. We came to the conclusion that the quieter the muffler, the lower the power output from the engine. Enclosures are the best way to go. Nice video.
If you reduce power, you have not built a good enough flowing muffler. What works better (on race cars for example) is a sound cancellation box instead of a muffler. RUclips David vizard, he has videos on building zero loss exhaust systems. Yes, they work.
@@h8troodoh Not really but that is also a great example of what an engine needs (two stroke/expansion chamber) An engine should have ZERO backpressure. ZERO! If you have backpressure, you are not getting 100% performance. (why manufacturers now use headers when before headers were only for "race or performance" applications). They improved efficiency, period. (this resulted in more power/better mileage/etc) A cancellation box takes the exh pulses and lets them go one way and sets up the resonance sent back to the exh valve to hit at the perfect time to cause scavenging. Not required on every engine in mundane duties, but the principals are the same regardless.
@lowrangeinnovascotia2930 I'd like to disagree on the zero back pressure, some engines require it,2 stroke piston port engines, for example, as the fuel air charge would be following the exhaust gates out the exhaust port so.. although they have designed deflectors on top of the pistons,the need for back pressure is still there. 40 year professional mechanic..🙂
We did the same thing. One night a young soldier on radio picquet heard it stop but did nothing about it. At reveille we found the we had harboured up in a dry river bed and the watertable had risen and drowned the genny. He got in trouble and the mechanics were really pissed off because they had to completely rebuild it as water had seeped inside the motor.
But remember if you restrict air flow your engine will not last long and if you add something like that big muffler it will add more back pressure and that will shorten engine and generator life ! I’m guessing that’s why his Subaru engine didn’t last because those things are bullet proof
People throw away things when they buy new ones, and free sheets of wood from a discarded cabinet are (for this purpose) every bit as good as new boards.
I can imagine most of the rude comments come from people that don't have what it takes to make videos to help people or they just hate people. But,, thank you for taking the time to PROVE it works and this is definatly an option. Good work.
sure, most of us have 'junk' which, after a while is not finding uses. Clean out my sheds, garage, would have enough for neighbors, too. just stack it around at an angle.....
In the Artillery we used a lot of generators. We buried them in the ground with sufficient room around the sides for them to breath. We then stacked sandbags around the side of the hole up past the top of the generator. we left breather holes in the sandbag formation. on the top of the sandbags we put plywood and covered the plywood with sandbags. you couldn't hear the generator until you were right up on it.
Same in the Royal Australian Artillery (of which I was a member for 20 years). In a pinch we use to put a flattened rations carton over the hole if we knew we wouldn't be in that gun position for very long.
Two observations; 1. If you do this in the summer, you run the risk of running a very hot engine and generator and causing a failure of each, or at least shortening the life of the unit. 2. You are allowing exhaust gasses to enter the intake- this will reduce the horsepower and also cause overloading and heating of the engine. Allow room for it to breathe! Build a large insulated box with diverted vents and even an exhaust fan.
Your not wrong, I tried something similar and when I shut it down I could hear a hissing noise, it was the fuel cap vent working to max, popped it off and removed the pre filter and the bottom of the tank was bubbling, literally boiling my fuel, God knows how much had just evaporated into the air🤦. Building a gasifier now to run it from but will keep the fuel side as well for a duel fuel setup and the tank I'm going to remove and mount away from the heat altogether.
I use acoustic ceiling boards, usually, I get them free when they are getting replaced. Just paint the outside white. The inside facing the genset absorbs the noise.
I lined my slightly angled box (deflection) interior with carpet pad (absorbstion) and reduced 22 decibels! Thanks so much for the simple but great demo and information!
I was thinking of doing something similar, but with “sound lining”, it’s an absorbent material about an inch thick. We use at work inside HVAC ducting..
Fantastic video. As a person who has had their hearing decimated by power tools , sirens and air horns , (retired firefighter) , I can definitely appreciate the value of your video. Losing your hearing affects your mood and sleep as well as ability to communicate with people. Great video.
People typically lose power in the winter months, if they have a hot tub it's normally drained, plywood to protect the floor, then throw the genny in there and the cover on with half folded open. Much quieter! And bonus..... you can wire- in a 2 way switch to your hot tub so the genny feeds power to the house through the 30 amp hot tub breaker once you've flipped the main off. Works slick!
65Ford, I learned a lot about acoustics from watching and reading some of the comments that were thoughtful. Thanks for the video. One way or another it will help me.
IKR? A 3 minute Demo would suffice. He explains what he is going to do 3x then what he did 3x then how this simple concept works 3x. "Hey, check this out: here's before: 80db. Lean a few boards against it: 70 db! 3 minutes max.
Very good idea. 3dB is a perceived doubling of amplitude (volume). Foil-backed constrained-layer butyl (Dynamat) is a panel dampner that lowers the resonant frequency of the surface it is adhered to. For a sound "barrier", mass-loaded vinyl is the product to use. To "de-couple" the MLV (mass-loaded vinyl) from a surface so sound isn't transfered via contact, closed-cell foam between the two is effective.
In construction we used to make a three sided box with a top and staple old carpeting to the plywood on the inside. The open side was away from us. Huge difference.
I kept the plywood it came with and sat it on top and went on Amazon and bought a patio furniture cover that fit, great for storing in garage. Makes a nice table too !
After being a guitarist and playing in car garages, sheds ect. some carpet padding (used) and easy to find as well as egg crates glued or nailed onto the wood pieces facing the Gen. could help knock the noise level down another 8 to 10 decibels easily for free and easy to set up take down without carrying a clunky dog house box around lol Great video Sixtyfiveford !!
Best generator shutter upper I've seen ! I've done all your tricks and it does work. I'm not done with sine wave cancellation, though. I think that's the key. Somehow. I also add a small cooling fan, plugged into the generator.
I used to run a generator on the back of my boat, to reduce exhaust noise I pushed a foot of copper pipe onto the exhaust tail, a 90° bend down the floor and then runs down into a small container of water. The exhaust gasses bubble through the water. Massive reduction in noise. It ran fine with no noticeable back pressure issues.
I know its work but I did-, I built a plywood box on 5 inch furniture wheels for my 3500W champion (cosco), cutout a 10 inch fan hole opposite exhaust end,- industrial fan from princess auto keeps the engine cooler on hot days, made a hinged hatch on top for pouring gas into tank, left an exhaust-roll in roll out genny hole to remove generator, used soundproof/ fireproof insulation inside stapled in with chicken wire, dropped 24-26 decibels-this was necessary for my use love it
All i kept thinking is "I wouldn't be able to believe if my neighbor was doing this in their *front yard* " No legit, great video. I just bought the Harbor Freight 4375W, learning any tips and tricks i can and I will absolutely be using this trick. Thanks, and subscribed!
This is a very nice video explanation. However, the author and most of the commentors have the physics of sound incorrect. As an acoustical expert i would point out the following. 1. a 3 dB reduction in the sound level is equal to a 50% reduction in the sound pressure level. 2. Where human listeners are concerned, it takes a 10 dB reduction in sound pressure to realize a 50% reduction in LOUDNESS. Loudness being the psychological aspect of sound and Sound Pressure being the physical aspect of sound.
Man, I love this video! Your decision to show the reduction in actual decibels as you put up those boards, with camera on the sound meter, is pure genius. A fellow just can't forget that after seeing it. If it wouldn't be too much of a pay cut, you might consider becoming a teacher. Awesome stuff! Thank you so much for sharing!
I will try this !!! Very easy 👌... thank you. My neighbor refuses to use his generator because he is afraid of making noise because of his neighbor will get mad at him. I will pass this on. Thax a bunch!! God bless! 👍
I used a Harley Davidson muffler on mine, and next morning there were a dozen Hell's Angels camped around my generator ... :) Seriously though, thanks for the demonstration ...
That would be true if you live far enough away from people otherwise you guys would have people who would want to steal your generator, I'm actually planning on using a type 1 VW 4 cylinder with a quiet muffler and a home built inverter generator and low rpm preferably 1800 rpm which is near idle speed with a belt driven governor for when loads change. So yes this issue would be a giant generator setup stationed in a garage or out building .
Thanks so much for such a simple solution. I've been fretting over which generator to get based on sound and this will open up so many options that I wasn't considering. Also thanks to the thoughtful comments and suggestions.
It's probably too late for this advice now but over 48 years as a mechanical engineer I've noticed that 'Honda engine' powered systems are consistently the quietest. On a side note, with proper maintenance they're also one of the most reliable and long lasting. Not a personal pitch for Honda just something that caught my attention!
I read in Patrick Kelly's book where he talks about a guy living off grid and wore out an expensive generator after mere months running it to charge his FLA battery bank when the Sun doesn't shine and the wind ain't turning his windmill. He noted that it had 120v and 240v sockets, which went to taps on the generator head stater. He said he ran his charger exclusively on the 120v socket, and being all the load was on the 120v side, the generator head was unbalanced, the engine was under uneven load, it ran loud, and the fuel consumption was high. And the thing DIED after some months. He bought another big gasoline generator, but he hooked a heavy industrial/commercial grade 240v/120v transformer to the 240v socket and ran all this 120v stuff on that, with the load on the generator head being balanced. The generator was quieter, it sipped fuel, and it lasted years without issue. Presumably it was still running good beyond the writing of the book.
Great video, I agree with the principle. I built an enclosure for my Champion 4.5 using ½" plywood. I lined the interior with Thermozite thermal acoustic barrier $25 (1)roll. I used a small soffit vent for ventilation. The results were unbelievable. My gen sits on the outside corner of my house and it went from ridiculous to a mild hum. Don't spend your $$ on so-called silencers, just enclose the unit. Total cost about $50 but it's a permanent enclosure!
I built a dog house for mine,it comes apart for camping. its really quiet. I have used a snowmobile exaust system too,it works much better than a car muffler and smaller. Dont use a really old one,use a newer one. I was surprised how much quieter it was using both.
Foil backed fiberglass duct board is fire proof light weight and should absorb sound you can find scraps at local HVAC installers dumpsters, if not big enough glue several pieces to thin plywood.
i had a gen like that with the suby engine and i ran it nearly constant for 3-4 months almost solid......then ran it 2 more months for atleast 18 hrs constant our a 24hr day.........it started using oil pretty bad but it still ran great.....i stiil have it....tore the engine down and it looks great on the inside.......rings are worn out, that was it........i was running my entire house with it....our power had gotten shut off.....i had unlimited gas for it cause i worked at a recycling yard and got all the gas out of junked cars that came in.......great engine in my opinion..........
The sound deadener you were referring to is asphalt. Asphalt "peel-and-stick" waterproofing would work pretty well and is available at a lot of supply houses. It's the same rubberized asphalt with an HDPE film instead of foil which would be more difficult to source and more expensive. Great tip! I'll be trying that at my off-grid deer camp.
@Paul E, what about "Wet or Dry" you get at home depot, would that work? It is a sticky black rubberized tar like substance you brush on thick to stop roof leaks, or water proof 4x4 posts in the ground. I also use it on white PVC vent pipes that stick out of roofs so they don't look as noticeable on black roofs - plus the thick rubber does not wear away as quickly as black paint.
@@paulromsky9527 I don't know. I think the principle of the rubberized asphalt is to attenuate the vibration from sound waves. I'm by no means an expert in acoustics but is seems to me to work that way. I would assume that a rubberized coating would work similarly. I do know that the auto manufacturers use a sheet rubberized asphalt composite for sound deadening. It's gets applied to places like the firewall which is stamped sheet metal. The asphalt reduces sound transmission.
Nice demo!!! My cherry bomb made a slight difference and in my original video,I ran it at the end and used an iPhone Db meter app that was not even close to being accurate. I eliminated that part of the video and I still get flack for that,even though I've used the generator in many other videos. I've been keeping my eye on Craigslist for one of those small rubber sheds that I plan on retrofitting a fan and some absorption batting into. Great vid!
BCtruck, rebuild, repair,repurpose Thanks Brad. Yeah, the arm chair engineers are watching every move we make..... I get a fair amount of flack for using a performance muffler in my old video. I tell people to throw the hood up on their car and have their wife peg it at 3600rpm and tell me how quiet their car is now.
Sixtyfiveford, you just gave me a good idea. I have a portable inverter generator I take camping. It's still loud at 20ft. Get an old doggie crate and line it with flame retardant Dynamat car sound deadening material. Leave one end open (for air circulation) and pointed towards the forest and away from campers. Thanks!!
your osb works better than ply because the panel has less resonance. they make guitars with plywood tops ("laminated soundboard"), but NEVER osb ones. if it has resonant qualities, it will pass the vibrations that match that resonance, and often amplify those frequencies. sheetrock, same same. if you're going to use ply, use thin panels, and "stand them off" in multiple layers with good double faced tape. inner ply mambos, tape absorbs a bit, so next panel just fox trots. repeat, next panel does a very sedate waltz. pipe foam insulation split tube foam on the panel edges would do about the same as double face tape does. that "white foam insulation" board between 2 layers of ply would be near ideal, but a potential fire hazard, and gasoline will make it "go houdini" (disappear like magic). the old time chevy nova "rubber carpet" would make a great isolation layer, as would those "hard rubber chain link style" door mats, while still allowing just about any fastening scheme to work. you could probably fashion a fairly efficient "breathing wall" for the intake side just out of such floor mats, staggered and properly angled, that would be just as good as ply, while passing far more air. window screening of "dead" varieties (like the plastic stuff) could probably do much of the same. for you folks mentioning "studio egg crate foam", it actually does only what the vid mentions, only both forms at once, in a cumulative deadening process (pyramid wall reflects sound while absorbing some vibration, sound wave is reflected into another pyramid wall, cycle repeats ad infinitum). just like bullets, and light, the "ricochets" tend to be at 90 degrees of the angle of incidence (the angle the wave strikes the panel at, in the natural direction you would expect such a ricochet), so by structuring "angle of incidence" you control where the wave goes. bounce it between enough dampeners (vibe absorbers), it "dies" the death of a thousand cuts.
Every 3db is a doubling of power so a 10db reduction is greater than 6x reduction in sound power. That's why there's so much difference between the before and after sounds. Probably been said already, I couldn't find it though, but it can't be said enough. Log scales are tricky. Great video.
Thank you so much for this. Our country, South Africa, is currently experiencing national rolling blackouts, 2.5 hours x 3 times a day, and my generator is too noisy to run at night. Just slapped together the soundbox with retainer bricks and old wood sheets and the results are amazing. We can actually use our generator without being inconsiderate twats to our neighbours now. (Nobody else has a generator due to a countrywide shortage).
Christopher Brunsdon same here! Also from SA. We rushed to Makro and there were only 2 generators left. We have some crappy times ahead of us here in SA......
@@Zeroa3337 my local Builders sold out within hours over the weekend. They had over 40 large generators in stock when I bought mine. Tough times ahead indeed.
Found this comment 3 years later and nothings changed haha. Just got a genny now and it’s too loud for my liking. Def going to look into some sound deflection and this seems like it’s worth a try. Some guys selling professional built soundproofing boxes as well nowadays
I like the way you've applied known principles to create a simple and practical solution, I'm definitely going to try this! (including the suggestion to incorporate sound absorbing materials). Great video, mate. Thanks.
Ron West lol, I guess the contractors should get power pole put in so we could build their houses! When I worked construction(sheet rock man) we always had neighbors complaining so we put 3 pieces of drywall around generator and that was about all we could do We also gave them the contractors card! lol!
Working in construction, we do the plywood trick all the time with our little generators when we're using them. Some of our larger diesel ones are already boxed in, so are pretty quiet, but we have a few ancient towable open-frame ones that are extremely loud. We try to stick them behind the sea-can or some other obstacle whenever possible, same idea, but bigger
Also, you just reminded me of something mentioning the square generator sheds. We've done a couple of school renovations, including music rooms. One of them had all of the walls on odd angles, nothing was quite square or plumb, and no large flat areas. Apparently it helps cut down on the echos considerably. It would look odd, but I wonder if that could be applied to making a generator shed?
By using a 3/4 nipple that fits into the exhuast port of the engine and stepping it up to 2"x12" nipple and then back down to 1/2" nipple you will have a very quiet motor depending on how long the 1/2" is.
Sounds like a tuned pipe silencer and correctly designed, they are very effective, but most of the noise from a four stroke air cooled engine is mechanical and is transmitted through the engine case to the surrounding air. This is why most fixed placement gensets use fluid cooled engines.
Bear U liquid cooled motors are not only quieter...but usually it's more fuel efficient too as a liquid cooled engine is easier to extract horsepower out of then a fan or free air motor without heat saturation issues.
When I was in the Army the Engineers used to bury them in a pit back in the rear for HQ, I have no idea how they did it or what they may have lined the pits with, but they were dead silent, you could stand on the top of the pit & not hear a thing & the Generators were in house built VW engines too!
sixtyfiveford but what happens when the ground absorbs all sound it can absorb, does it get noisy again??? calm down people it's a freekin joke. cool videos broseph, keep um comin.
Excellent empirical engineering! The secret is LAYERING with various materials. The more layers, the more diverse materials ... the more attenuation. Thickness, distancing & geometry are more about redirecting the energy and filtering. Forcing energy to make the transition from one type of material to another is where the dampening occurs ... applicable to DC through 'daylight', seismic to cosmic. They all behave like waves of particles.
You're mostly correct about layering and different materials being effective but the underlying reasons aren't understood by most. First of all, separate layers are good primarily because of 'decoupling' (inhibiting physical transfer of sound wave energy into and through the barrier via vibration) and also 'dampening' the presumably flat, rigid surface which in turn adds mass and reduces transmitted vibrations, especially above low frequencies. Those are the 2 main reasons layers are helpful regardless of material but lower frequencies are much harder to simply deflect with a hard surface and need a relatively thick layer of soft, low density material like foam, very thick carpet or similar. It's important to know that it's very easy to block mid-high frequencies with any rigid surface but, like drywall in a house for example, lower frequencies and especially bass frequencies (
Hot exhaust blowing on flammable plywood and restricting air flow necessary to cool the air cooled engine. It's will make a lot less noise when the engine locks up, or bursts into flames. Great job.
cubbeezx Yes. It changes the perception of a "clock" to a time meter; of which it really is. I similarly put an analog clock on my furnace to monitor its runtime (powered a receptacle off of the vent blower power (only minimal wattage allowed)). An earth day, earth's single rotation, seems to lose reference quickly if one would be in the space station which circles the earth 5 times (?) a day.
I looked, but the clock was blurry and not yet plugged in, so I still didn't see much of anything. I can't figure out why he would cover up that part of the video.
Also run a 5k powermate with the suby engine... Its about 10 years old and has been providing power to my cabin for that long.. Gets a once a year oil change.. Runs anywhere from 3-10hours friday and sat... Id say about 60-70 tank fulls of gas each year
Great video and thanks for the good idea, I just have to say that a reduction of 3 dB is the same as reducing the sound by half, but for the human being to feel it half as laud, you have to reduce it by 10 dB.
** A 3 sided dog house , works so well for us. 4 corner Posts - Humped Roof w/shingles, dirt floor. 👌🏼 can’t hear much from behind or from either side. Only from the front. the wood walls muffle much of the noise. Don’t waste yer time on anything else. Tip it backwards to check oil/gas.
Nice tip, thanks man. A cool experiment would be to line the plywood sheets with the thin sound/heat insulation stuff like Dynomat, used on car interiors. Of course that would increase the budget but might make it even more quiet.
Ozzstar I tested out some rubber matting(conveyor belt) with good results. I almost bought a couple rolls of the foil/tar at the Home Depot(dynomat rip-off) but this worked so well in the testing I figured it would only be good for another 1-2db.
You are correct. Everyone on youtube who has ideas to run something quiter says to smother it. They will run much hotter. If it was a good idea you would think the mfg would recommend that you leave them in the box they are shipped in.
Dig below ground and install generator, with an appropriate air gap and let earth muffle the sound..... This simple method is used in some residential areas without mains power supply.... Takes longer than your 10 minutes of course ....
Hey I was wondering are we going to talk about the video up today or go on and on about a muffler which has nothing to do with todsy. Hey why don’t you go thru the list of videos that have nothing to do w this video get all your links at the bottom im gonna keep searching for a video about reducing sound on my generator only and I’ll pass back in 20 min or so to see if your finished listening to you voice and watching uourself on tv. Thanks for the muffler tips im positive I’ll never think about it again. If I go to your muffler video you think your generator info is there bc it’s not here
From my engineering classes, -3 dB cuts the sound in half. So a 9 dB reduction is about 1/8th. The formula for 10 dB would be 1÷(2^(10/3)) = 0.099 or 1/10th. So you made a huge improvement.
Very interesting video..thanks for sharing. From my experience, the only Robin / Subaru small engine that I've seen quit running were ones that were severely neglected. I saw one that was run with no oil till it knocked, then they put oil in it and it ran for a long time afterwards, knocking away for about a year. That was on a gas air compressor!
D. J. Tanner This one double failed. The oil level sensor that is supposed to shut off the engine when the oil is low, died and would not allow the engine to start. So the original owner pulled the kill wire to this sensor so it could be run. He sold it to a guy(never told him this was unplugged) who figured it had the low oil shut down so he never needed to check the oil.... wham bam bang, there's no longer a piston rod and she's mine now.
D. J. Tanner I am a believer in Subaru products. They have proven themselves over and over again.I have a 1995 wagon with over 500.000 miles and still going strong.
*****, I love anything Subaru. Our first Subaru when I was 10 years old, was a 1979 GL 1600 4wd Wagon. It's was tough, dependable and so fuel efficient and went like a tank in snow. Subaru customer loyalty is amazing! My fiancé will only drive Subaru vehicles.
D. J. Tanner I've seen quite a few of them die for no reason,and have gotten some great deals due to their failures..I would not buy anything with one of them on it unless the deal was practically a gimme,or good enough to compensate for the new engine that I am going to have to put into it before too long...
I've owned 3 Subaru 1 Nissan and 1 Toyota and 1 Honda, the Honda was the only one who blew the tranny. I'm not saying hondas are bad but Subarus make excellent products.
As a mechanic this is not advisable . Generation units are designed at there max to preform . Restricted airflow with a cover will heat the engine and gen set. My advise keep a good factor high flow muffler on it and use a good cord that's heavy and long lol
I do a similar thing, temporarily, for my General. But also have built another version which provides about 3-ft spacing for fire protection and ability to redirect the sound into a particular direction into the dense forest. But this still leads to poor airflow for cooling. Even at -8F, the sound box will heat up to the 70’s, imagine when it is +80F. We live off grid and do what we can to use the gens the least and the quietest. We will be enlargening the sound box and adding studio egg crate foam, hopefully before the winter.
I built a 1 end, and one side box with a floor and hinged top out of plywood. So one open end and one open side. The top, side and end were lined with 1 1/2" styrofoam insulation. The exhaust side was facing the open side of box. The open end made it possible to roll the generator into the box. The hinged top made it possible to refuel easily. This was for my camp with a 5000w gen. The exhaust side faced the woods behind the camp. Worked well.
Hello! Great video! It's almost what I've done. But I take a 1" thick piece of fire proof sound foam that I glued to the particle board, with a thick moving blanket folded up right on top of it all, just like you did at angles. That works unbelievable well! I do not have a dbl meter , but it is much much quieter. Plus everything just lays down flat to take up almost no space. In windy areas I use a cargo net over the whole thing, with spikes set into the ground to hold everything in place. But at home I just made a nice weather proof box, with the same fireproof sound foam.
Awesome. I like the fireproof foam. That should drop the sound dramatically.
Kevin Voyer they have decibel meter apps 👍
K. R. V. I
Hey KRV! Can you possibly post photos of your matierals or a shopping list of them and how you place them to the generator... I just got my generator and your setup sounds greaT!! Thank you!!!
K. R. V. k
I did this to my wife, and man ! Does this work !!!
Which end did you install it on?
Lol
Ha! I see what you did there.
Good one man!
I got hearing aids and turned them off to achieve the same thing.
And I don’t need hearing aids.
Nice video showing that most generator noise is not always just the exhaust. The doghouse method of noise reduction has been used by commercial home generator companies for decades with great success. Your boards deflect most of the noise into the ground where much of it is absorbed. Simple, cheap and effective. We did a lot of exhaust modifications to small engines in an attempt to quiet them and not reduce power. We came to the conclusion that the quieter the muffler, the lower the power output from the engine. Enclosures are the best way to go. Nice video.
If you reduce power, you have not built a good enough flowing muffler. What works better (on race cars for example) is a sound cancellation box instead of a muffler. RUclips David vizard, he has videos on building zero loss exhaust systems. Yes, they work.
@@lowrangeinnovascotia2930 are you referring to megaphone( or tuned) pipes like on racing two stroke engines? Use of soundwaves for back pressure??
@@h8troodoh Not really but that is also a great example of what an engine needs (two stroke/expansion chamber)
An engine should have ZERO backpressure. ZERO! If you have backpressure, you are not getting 100% performance. (why manufacturers now use headers when before headers were only for "race or performance" applications). They improved efficiency, period. (this resulted in more power/better mileage/etc)
A cancellation box takes the exh pulses and lets them go one way and sets up the resonance sent back to the exh valve to hit at the perfect time to cause scavenging. Not required on every engine in mundane duties, but the principals are the same regardless.
@lowrangeinnovascotia2930 I'd like to disagree on the zero back pressure, some engines require it,2 stroke piston port engines, for example, as the fuel air charge would be following the exhaust gates out the exhaust port so.. although they have designed deflectors on top of the pistons,the need for back pressure is still there. 40 year professional mechanic..🙂
In the Army, we put our generators in a hole in the ground or a berm of sand bags....Reduced the noise and makes the generator much harder to locate
kbbacon Makes perfect sense.
+kbbacon We did same in Russian army.
+kbbacon It would drown where I live. ;)
However, I could make a little berm to conceal it I guess.
ltyr2001 1 We burmed in Louisiana.
We did the same thing. One night a young soldier on radio picquet heard it stop but did nothing about it. At reveille we found the we had harboured up in a dry river bed and the watertable had risen and drowned the genny. He got in trouble and the mechanics were really pissed off because they had to completely rebuild it as water had seeped inside the motor.
I have been researching inexpensive ways to quiet a generator and this video is by far the best I've come across. Thank you so so much.
Probably too late for it but you should look into hush houses. We use them for jet engine testing indoors
But remember if you restrict air flow your engine will not last long and if you add something like that big muffler it will add more back pressure and that will shorten engine and generator life !
I’m guessing that’s why his Subaru engine didn’t last because those things are bullet proof
In 2021, that’s a $200 enclosure. Hopefully wood prices come down at some point soon!
(Ok, maybe I’m exaggerating, but close)
I don't think you're very far off the mark
I was so bummed when I saw the payoff was using sheets of wood, guess we're all just 6yrs too late
People throw away things when they buy new ones, and free sheets of wood from a discarded cabinet are (for this purpose) every bit as good as new boards.
In 2024 thats a 1200$ enclosure 😂
I can imagine most of the rude comments come from people that don't have what it takes to make videos to help people or they just hate people. But,, thank you for taking the time to PROVE it works and this is definatly an option. Good work.
Thanks, I'm glad you liked it.
Seriously? So just pile sh!t around it is your solution to a quieter generator. Genius!
Hahaha those are the exact words I said when I saw this video! "So... just pile some shit on it?"
lol hey it works
sure, most of us have 'junk' which, after a while is not finding uses. Clean out my sheds, garage, would have enough for neighbors, too. just stack it around at an angle.....
When I was in the army a "tactical quiet generator" was a Honda generator placed in a pit in the ground.
It worked
In the Artillery we used a lot of generators. We buried them in the ground with sufficient room around the sides for them to breath. We then stacked sandbags around the side of the hole up past the top of the generator. we left breather holes in the sandbag formation. on the top of the sandbags we put plywood and covered the plywood with sandbags. you couldn't hear the generator until you were right up on it.
+george washington I would imagine the sand/dirt would absorb sound very well.
Naw- you all were just deaf.
Same in the Royal Australian Artillery (of which I was a member for 20 years). In a pinch we use to put a flattened rations carton over the hole if we knew we wouldn't be in that gun position for very long.
thats what we did.
Combat engineer 🇨🇦 .Same idea.2 rows of sanbags 🐌 shell design.
Two observations; 1. If you do this in the summer, you run the risk of running a very hot engine and generator and causing a failure of each, or at least shortening the life of the unit.
2. You are allowing exhaust gasses to enter the intake- this will reduce the horsepower and also cause overloading and heating of the engine.
Allow room for it to breathe! Build a large insulated box with diverted vents and even an exhaust fan.
Or just stick a $5 box fan under the plywood to assist with air flow if your worried about circulation.
All true, just remember powering the fan will reduce a little of the already limited available electrical power.
Your not wrong, I tried something similar and when I shut it down I could hear a hissing noise, it was the fuel cap vent working to max, popped it off and removed the pre filter and the bottom of the tank was bubbling, literally boiling my fuel, God knows how much had just evaporated into the air🤦. Building a gasifier now to run it from but will keep the fuel side as well for a duel fuel setup and the tank I'm going to remove and mount away from the heat altogether.
I use acoustic ceiling boards, usually, I get them free when they are getting replaced. Just paint the outside white. The inside facing the genset absorbs the noise.
I lined my slightly angled box (deflection) interior with carpet pad (absorbstion) and reduced 22 decibels! Thanks so much for the simple but great demo and information!
That's impressive!
MRrwmac @
I was thinking of doing something similar, but with “sound lining”, it’s an absorbent material about an inch thick. We use at work inside HVAC ducting..
Could you put the carpet pad on the ground under the generator? Will that absorb even more sound? My generator will be sitting on concrete. Thank you!
@@xyladivine yes
Fantastic video. As a person who has had their hearing decimated by power tools , sirens and air horns , (retired firefighter) , I can definitely appreciate the value of your video. Losing your hearing affects your mood and sleep as well as ability to communicate with people. Great video.
Don’t forget to watch this video about generator safety ruclips.net/video/I1jT3ANENvI/видео.html
People typically lose power in the winter months, if they have a hot tub it's normally drained, plywood to protect the floor, then throw the genny in there and the cover on with half folded open. Much quieter! And bonus..... you can wire- in a 2 way switch to your hot tub so the genny feeds power to the house through the 30 amp hot tub breaker once you've flipped the main off. Works slick!
WHY ON EARTH would you EMPTY your HOT TUB in the winter? it's LITERALLY the BEST TIME to use one!
@@davidmichael7756 The Polar Bear Club👍
65Ford, I learned a lot about acoustics from watching and reading some of the comments that were thoughtful. Thanks for the video. One way or another it will help me.
Thanks, I'm glad you liked the video.
Smart use of acoustics, damn cost effective too! Wrap and staple some old carpet to those boards & knock off even more notable dB's.
Be sure to monitor temps. Restricting the airflows can soon lead to overheating.
Did you watch the video? He mentions airflow…
@@JosephQPublic LOL he restricted air flow that means the generator is running hotter than normal get it???
Almost a decade old and still useful information. Thank you
You bet!
Why it took 10:34 minutes to explain something that can be done in 10 seconds??????
I cheated and skipped ahead.
It is normal for an explanation of a process, to take far longer than the process itself.
Same reason your girlfriend likes it when I take 10:34 to explain what takes you just 10 seconds.
@@duronboy2 it takes me 8 seconds
IKR? A 3 minute Demo would suffice. He explains what he is going to do 3x then what he did 3x then how this simple concept works 3x. "Hey, check this out: here's before: 80db. Lean a few boards against it: 70 db! 3 minutes max.
Very good idea. 3dB is a perceived doubling of amplitude (volume). Foil-backed constrained-layer butyl (Dynamat) is a panel dampner that lowers the resonant frequency of the surface it is adhered to. For a sound "barrier", mass-loaded vinyl is the product to use. To "de-couple" the MLV (mass-loaded vinyl) from a surface so sound isn't transfered via contact, closed-cell foam between the two is effective.
In construction we used to make a three sided box with a top and staple old carpeting to the plywood on the inside. The open side was away from us. Huge difference.
Love the Ford 4x4 in the background! Great video as well.
How ironic is it that right as I get to your comment while scrolling, the 4x4 Ford makes its appearance?!?
Nice! Was planning to build an enclosure for mine with a powered fan, but I had not considered using sheetrock as a liner. Thanks for the idea!
My generator is quiet but that's mostly because I struggle to get it running half the time
airkraft1 Haha.. Yeah, they don't make much noise then.
sixtyfiveford
Nope
Before shut down, turn off fuel line to drain carb. Will start easier.
It's real quiet if you just keep pulling the starter cord to "run" the generator with the ignition off... good shoulder workout too.
Lol
That osb is deflecting and absorbing because of the particle press. Never thought of that. Thanks for being so thorough and creative.
Thanks for watching!
I kept the plywood it came with and sat it on top and went on Amazon and bought a patio furniture cover that fit, great for storing in garage. Makes a nice table too !
What about the Tremors? They’ll feel the vibration and eat it right away!
You mean the Graboids I thunk
The spice worms you mean?
@@MrKWiley918 No they're called Graboids
Ass Blasters too ....ha !
Snakoids people SNAKEOIDS 🤣🤣🤣
After being a guitarist and playing in car garages, sheds ect. some carpet padding (used) and easy to find as well as egg crates glued or nailed onto the wood pieces facing the Gen. could help knock the noise level down another 8 to 10 decibels easily for free and easy to set up take down without carrying a clunky dog house box around lol Great video Sixtyfiveford !!
+Aaron Manderscheid I've done that. Had a low cost recording studio for a while which had egg cartons for the acoustic tiles.
Lynn Magnuson Yeah egg cartons and foam padding from Apartments or homes that were getting re-carpeted ! Worked really really well ...
9
Aaron #The80'sRocked Good idea! Thx.
Good idea
I can say this because I'm from the Philippines. That is Filipino rigging at it's finest. Salamat!
Glad you like it. Thanks.
Anyone should be able to say it without being labeled racist.
Best generator shutter upper I've seen ! I've done all your tricks and it does work.
I'm not done with sine wave cancellation, though. I think that's the key. Somehow.
I also add a small cooling fan, plugged into the generator.
I used to run a generator on the back of my boat, to reduce exhaust noise I pushed a foot of copper pipe onto the exhaust tail, a 90° bend down the floor and then runs down into a small container of water. The exhaust gasses bubble through the water. Massive reduction in noise. It ran fine with no noticeable back pressure issues.
Congratulations 65 ! You're hitting these fundamentals and concepts accurately.
I know its work but I did-, I built a plywood box on 5 inch furniture wheels for my 3500W champion (cosco), cutout a 10 inch fan hole opposite exhaust end,- industrial fan from princess auto keeps the engine cooler on hot days, made a hinged hatch on top for pouring gas into tank, left an exhaust-roll in roll out genny hole to remove generator, used soundproof/ fireproof insulation inside stapled in with chicken wire, dropped 24-26 decibels-this was necessary for my use love it
***** Sounds like a great generator shed.
i do this every time i camp with a generator , been using this trick for years , works great !
All i kept thinking is "I wouldn't be able to believe if my neighbor was doing this in their *front yard* "
No legit, great video. I just bought the Harbor Freight 4375W, learning any tips and tricks i can and I will absolutely be using this trick. Thanks, and subscribed!
... and it looks so beautiful. Your neighbors must love it! 😖
This is a very nice video explanation. However, the author and most of the commentors have the physics of sound incorrect. As an acoustical expert i would point out the following. 1. a 3 dB reduction in the sound level is equal to a 50% reduction in the sound pressure level. 2. Where human listeners are concerned, it takes a 10 dB reduction in sound pressure to realize a 50% reduction in LOUDNESS. Loudness being the psychological aspect of sound and Sound Pressure being the physical aspect of sound.
Is that why it seems to be half as loud?
no one gives a shit
As stupid as it may seem, this deserves a like. It's ingenious and so simple? Cheers
Man, I love this video! Your decision to show the reduction in actual decibels as you put up those boards, with camera on the sound meter, is pure genius. A fellow just can't forget that after seeing it. If it wouldn't be too much of a pay cut, you might consider becoming a teacher. Awesome stuff! Thank you so much for sharing!
+Jaddie Dodd Thank you very much.
Just purchased a generator. You presented a simple solution to reducing noise. Thanks.
Thanks for watching.
I will try this !!! Very easy 👌... thank you. My neighbor refuses to use his generator because he is afraid of making noise because of his neighbor will get mad at him. I will pass this on. Thax a bunch!! God bless! 👍
Thanks, I'm glad you liked it.
I'm in the same situation. I can use it in emergency and only for short time. In the meantime, my food spoils
I used a Harley Davidson muffler on mine, and next morning there were a dozen Hell's Angels camped around my generator ... :)
Seriously though, thanks for the demonstration ...
Haha. Thanks for watching.
Lol. Sweet
fossicker2000 😂😂😂😂
Sorry but real Harley Davidsons dont have mufflers 🤠
How long did it run before it broke. down
During an emergency which is the only time I would have to use my generator the sound is the last of my worries.
true
That would be true if you live far enough away from people otherwise you guys would have people who would want to steal your generator, I'm actually planning on using a type 1 VW 4 cylinder with a quiet muffler and a home built inverter generator and low rpm preferably 1800 rpm which is near idle speed with a belt driven governor for when loads change. So yes this issue would be a giant generator setup stationed in a garage or out building .
Thanks so much for such a simple solution. I've been fretting over which generator to get based on sound and this will open up so many options that I wasn't considering. Also thanks to the thoughtful comments and suggestions.
It's probably too late for this advice now but over 48 years as a mechanical engineer I've noticed that 'Honda engine' powered systems are consistently the quietest.
On a side note, with proper maintenance they're also one of the most reliable and long lasting. Not a personal pitch for Honda just something that caught my attention!
I read in Patrick Kelly's book where he talks about a guy living off grid and wore out an expensive generator after mere months running it to charge his FLA battery bank when the Sun doesn't shine and the wind ain't turning his windmill. He noted that it had 120v and 240v sockets, which went to taps on the generator head stater. He said he ran his charger exclusively on the 120v socket, and being all the load was on the 120v side, the generator head was unbalanced, the engine was under uneven load, it ran loud, and the fuel consumption was high. And the thing DIED after some months.
He bought another big gasoline generator, but he hooked a heavy industrial/commercial grade 240v/120v transformer to the 240v socket and ran all this 120v stuff on that, with the load on the generator head being balanced. The generator was quieter, it sipped fuel, and it lasted years without issue. Presumably it was still running good beyond the writing of the book.
Great video, I agree with the principle.
I built an enclosure for my Champion 4.5 using ½" plywood. I lined the interior with Thermozite thermal acoustic barrier $25 (1)roll. I used a small soffit vent for ventilation. The results were unbelievable. My gen sits on the outside corner of my house and it went from ridiculous to a mild hum.
Don't spend your $$ on so-called silencers, just enclose the unit.
Total cost about $50 but it's a permanent enclosure!
I'm digging that Ford 4X4...
Beautiful truck
That was awesome man, you wouldn't think someone would need to make a video like that but I tend to make things way too complicated so thank you
I built a dog house for mine,it comes apart for camping. its really quiet. I have used a snowmobile exaust system too,it works much better than a car muffler and smaller. Dont use a really old one,use a newer one. I was surprised how much quieter it was using both.
hey right on, did the same. Works well to keep the snow off it too. And it's pretty secure inside it.
Foil backed fiberglass duct board is fire proof light weight and should absorb sound you can find scraps at local HVAC installers dumpsters, if not big enough glue several pieces to thin plywood.
This was a really well done demo! Liked watching the decibels change on the meter as each wall went up.
i had a gen like that with the suby engine and i ran it nearly constant for 3-4 months almost solid......then ran it 2 more months for atleast 18 hrs constant our a 24hr day.........it started using oil pretty bad but it still ran great.....i stiil have it....tore the engine down and it looks great on the inside.......rings are worn out, that was it........i was running my entire house with it....our power had gotten shut off.....i had unlimited gas for it cause i worked at a recycling yard and got all the gas out of junked cars that came in.......great engine in my opinion..........
Gary Marshall you environment killer.
I'm doing the same thing and mine has quite no compression and want start
@@michaelpalmer4160 when these are barricaded the air doesnt cool it properly! Kills the engines
Love your 70's Ford truck
I wish my lawn looked that good.
+dmmadde Thanks...
Search LCN
Looks like a carpet
Super useful stuff to know! Glass packs are often used as resonators on OEM car exhaust
The sound deadener you were referring to is asphalt. Asphalt "peel-and-stick" waterproofing would work pretty well and is available at a lot of supply houses. It's the same rubberized asphalt with an HDPE film instead of foil which would be more difficult to source and more expensive. Great tip! I'll be trying that at my off-grid deer camp.
@Paul E, what about "Wet or Dry" you get at home depot, would that work? It is a sticky black rubberized tar like substance you brush on thick to stop roof leaks, or water proof 4x4 posts in the ground. I also use it on white PVC vent pipes that stick out of roofs so they don't look as noticeable on black roofs - plus the thick rubber does not wear away as quickly as black paint.
@@paulromsky9527 I don't know. I think the principle of the rubberized asphalt is to attenuate the vibration from sound waves. I'm by no means an expert in acoustics but is seems to me to work that way. I would assume that a rubberized coating would work similarly. I do know that the auto manufacturers use a sheet rubberized asphalt composite for sound deadening. It's gets applied to places like the firewall which is stamped sheet metal. The asphalt reduces sound transmission.
@@paulromsky9527youbare talking about mastic. And that would be a messy job. Upload a video. Lol
Nice demo!!! My cherry bomb made a slight difference and in my original video,I ran it at the end and used an iPhone Db meter app that was not even close to being accurate. I eliminated that part of the video and I still get flack for that,even though I've used the generator in many other videos. I've been keeping my eye on Craigslist for one of those small rubber sheds that I plan on retrofitting a fan and some absorption batting into. Great vid!
BCtruck, rebuild, repair,repurpose Thanks Brad. Yeah, the arm chair engineers are watching every move we make..... I get a fair amount of flack for using a performance muffler in my old video. I tell people to throw the hood up on their car and have their wife peg it at 3600rpm and tell me how quiet their car is now.
And now you have the shed. :-)
Looking forward to seeing your adaptations for shed & your new generator.
@@oldtimerlee8820 hello from 6 years ago!! Only took me 6 years to get the shed.
Fiberglass Ceiling tiles with the PLASTIC side removed should work like a GOLD MEDAL CHAMPION!
Old carpet stapled onto The underside of the plywood will reduce sound even more
Stapled to the outside would be safer.
@@jamesrodgers3132 But then in rain or snow it would get wet and moldy.
Sixtyfiveford, you just gave me a good idea. I have a portable inverter generator I take camping. It's still loud at 20ft. Get an old doggie crate and line it with flame retardant Dynamat car sound deadening material. Leave one end open (for air circulation) and pointed towards the forest and away from campers. Thanks!!
One year on: how well did that work?
Good suggestions! The hour meter at the end made it even better. I am gonna put one on my lawn tractor.
your osb works better than ply because the panel has less resonance. they make guitars with plywood tops ("laminated soundboard"), but NEVER osb ones. if it has resonant qualities, it will pass the vibrations that match that resonance, and often amplify those frequencies. sheetrock, same same. if you're going to use ply, use thin panels, and "stand them off" in multiple layers with good double faced tape. inner ply mambos, tape absorbs a bit, so next panel just fox trots. repeat, next panel does a very sedate waltz. pipe foam insulation split tube foam on the panel edges would do about the same as double face tape does. that "white foam insulation" board between 2 layers of ply would be near ideal, but a potential fire hazard, and gasoline will make it "go houdini" (disappear like magic). the old time chevy nova "rubber carpet" would make a great isolation layer, as would those "hard rubber chain link style" door mats, while still allowing just about any fastening scheme to work. you could probably fashion a fairly efficient "breathing wall" for the intake side just out of such floor mats, staggered and properly angled, that would be just as good as ply, while passing far more air. window screening of "dead" varieties (like the plastic stuff) could probably do much of the same.
for you folks mentioning "studio egg crate foam", it actually does only what the vid mentions, only both forms at once, in a cumulative deadening process (pyramid wall reflects sound while absorbing some vibration, sound wave is reflected into another pyramid wall, cycle repeats ad infinitum). just like bullets, and light, the "ricochets" tend to be at 90 degrees of the angle of incidence (the angle the wave strikes the panel at, in the natural direction you would expect such a ricochet), so by structuring "angle of incidence" you control where the wave goes. bounce it between enough dampeners (vibe absorbers), it "dies" the death of a thousand cuts.
Every 3db is a doubling of power so a 10db reduction is greater than 6x reduction in sound power. That's why there's so much difference between the before and after sounds. Probably been said already, I couldn't find it though, but it can't be said enough. Log scales are tricky. Great video.
Thank you so much for this. Our country, South Africa, is currently experiencing national rolling blackouts, 2.5 hours x 3 times a day, and my generator is too noisy to run at night. Just slapped together the soundbox with retainer bricks and old wood sheets and the results are amazing. We can actually use our generator without being inconsiderate twats to our neighbours now. (Nobody else has a generator due to a countrywide shortage).
Christopher Brunsdon same here! Also from SA. We rushed to Makro and there were only 2 generators left. We have some crappy times ahead of us here in SA......
@@Zeroa3337 my local Builders sold out within hours over the weekend. They had over 40 large generators in stock when I bought mine. Tough times ahead indeed.
Wow I hope everything is better for you! Much love and respect!
Sounds like you boys need to do some affirmative action on Zuma's stockpile...........
Found this comment 3 years later and nothings changed haha. Just got a genny now and it’s too loud for my liking. Def going to look into some sound deflection and this seems like it’s worth a try. Some guys selling professional built soundproofing boxes as well nowadays
Thanks for the broad idea, particularly the angled surfaces.
Execution, as usual, is a bit of a beast - especially if it is to be durable.
Fantastic video. Got major inspiration now for my overly noisy “silent” Hyundai 6KW generator which I use on film sets. Thank you 🙏🏻
I like the way you've applied known principles to create a simple and practical solution, I'm definitely going to try this! (including the suggestion to incorporate sound absorbing materials).
Great video, mate. Thanks.
It’s easier than most of what the Jack wads on you tube do, and it’s easy venting.👍👍
Congrats, you scientifically proved what carpenters learned the first day the portable generator showed up on the first job site.
B Henry ya got me there. Don't know what bug I had up my keester that day but you're right.
Cheap gens on job sites could wake the dead.
Brad Smith I
Ron West lol, I guess the contractors should get power pole put in so we could build their houses! When I worked construction(sheet rock man) we always had neighbors complaining so we put 3 pieces of drywall around generator and that was about all we could do We also gave them the contractors card! lol!
Brad Smith
lol
Watching those dbs drop on the equipment was awesome. Cool video!
Working in construction, we do the plywood trick all the time with our little generators when we're using them. Some of our larger diesel ones are already boxed in, so are pretty quiet, but we have a few ancient towable open-frame ones that are extremely loud. We try to stick them behind the sea-can or some other obstacle whenever possible, same idea, but bigger
Also, you just reminded me of something mentioning the square generator sheds. We've done a couple of school renovations, including music rooms. One of them had all of the walls on odd angles, nothing was quite square or plumb, and no large flat areas. Apparently it helps cut down on the echos considerably. It would look odd, but I wonder if that could be applied to making a generator shed?
Sixtyfive!? Your grass is on point 😂🙌🏽
Thanks.
By using a 3/4 nipple that fits into the exhuast port of the engine and stepping it up to 2"x12" nipple and then back down to 1/2" nipple you will have a very quiet motor depending on how long the 1/2" is.
Sounds like a tuned pipe silencer and correctly designed, they are very effective, but most of the noise from a four stroke air cooled engine is mechanical and is transmitted through the engine case to the surrounding air. This is why most fixed placement gensets use fluid cooled engines.
Bear U liquid cooled motors are not only quieter...but usually it's more fuel efficient too as a liquid cooled engine is easier to extract horsepower out of then a fan or free air motor without heat saturation issues.
When I was in the Army the Engineers used to bury them in a pit back in the rear for HQ, I have no idea how they did it or what they may have lined the pits with, but they were dead silent, you could stand on the top of the pit & not hear a thing & the Generators were in house built VW engines too!
The ground is a great sound absorber.
sixtyfiveford
but what happens when the ground absorbs all sound it can absorb, does it get noisy again???
calm down people it's a freekin joke. cool videos broseph, keep um comin.
Excellent empirical engineering! The secret is LAYERING with various materials. The more layers, the more diverse materials ... the more attenuation. Thickness, distancing & geometry are more about redirecting the energy and filtering. Forcing energy to make the transition from one type of material to another is where the dampening occurs ... applicable to DC through 'daylight', seismic to cosmic. They all behave like waves of particles.
You're mostly correct about layering and different materials being effective but the underlying reasons aren't understood by most. First of all, separate layers are good primarily because of 'decoupling' (inhibiting physical transfer of sound wave energy into and through the barrier via vibration) and also 'dampening' the presumably flat, rigid surface which in turn adds mass and reduces transmitted vibrations, especially above low frequencies. Those are the 2 main reasons layers are helpful regardless of material but lower frequencies are much harder to simply deflect with a hard surface and need a relatively thick layer of soft, low density material like foam, very thick carpet or similar. It's important to know that it's very easy to block mid-high frequencies with any rigid surface but, like drywall in a house for example, lower frequencies and especially bass frequencies (
Hot exhaust blowing on flammable plywood and restricting air flow necessary to cool the air cooled engine. It's will make a lot less noise when the engine locks up, or bursts into flames. Great job.
Cool demonstration, that really made it a lot quieter! I like your hour meter at the end! lol
***** Thanks Man..
cubbeezx Yes. It changes the perception of a "clock" to a time meter; of which it really is. I similarly put an analog clock on my furnace to monitor its runtime (powered a receptacle off of the vent blower power (only minimal wattage allowed)). An earth day, earth's single rotation, seems to lose reference quickly if one would be in the space station which circles the earth 5 times (?) a day.
you can't see the hour meter because 4adds in in each corner pop-up right at that time and obscure the whole area
Stop the vid @ 10:13 and you can see it is a clock with the Pink Panther on a scooter with neon light around the edges.
I looked, but the clock was blurry and not yet plugged in, so I still didn't see much of anything. I can't figure out why he would cover up that part of the video.
Also run a 5k powermate with the suby engine... Its about 10 years old and has been providing power to my cabin for that long.. Gets a once a year oil change.. Runs anywhere from 3-10hours friday and sat... Id say about 60-70 tank fulls of gas each year
Great video and thanks for the good idea, I just have to say that a reduction of 3 dB is the same as reducing the sound by half, but for the human being to feel it half as laud, you have to reduce it by 10 dB.
** A 3 sided dog house , works so well for us. 4 corner Posts - Humped Roof w/shingles, dirt floor. 👌🏼
can’t hear much from behind or from either side. Only from the front. the wood walls muffle much of the noise.
Don’t waste yer time on anything else. Tip it backwards to check oil/gas.
About 5:40 in found out how the Subaru motor blue up.
Nice tip, thanks man. A cool experiment would be to line the plywood sheets with the thin sound/heat insulation stuff like Dynomat, used on car interiors. Of course that would increase the budget but might make it even more quiet.
Ozzstar I tested out some rubber matting(conveyor belt) with good results. I almost bought a couple rolls of the foil/tar at the Home Depot(dynomat rip-off) but this worked so well in the testing I figured it would only be good for another 1-2db.
One big problem, in high temperatures, like 85 and above, you restrict air from cooling, an air cooled machine.
You are correct. Everyone on youtube who has ideas to run something quiter says to smother it. They will run much hotter. If it was a good idea you would think the mfg would recommend that you leave them in the box they are shipped in.
You can deflect sound without blocking all airflow.
Throwing a crate over it with one open end facing away from you does wonders also and keeps the elements off of it.
Cool. Love the hourmeter!
I just turn up my stereo and cant hear it anymore
Happens for rattly, squeaky old cars too. Just turn up the stereo. No stereo- Don't buy it!
Dig below ground and install generator, with an appropriate air gap and let earth muffle the sound..... This simple method is used in some residential areas without mains power supply.... Takes longer than your 10 minutes of course ....
That would work really well.
Watch out if it rains though.
If you own property, that will work at home. Not so much when I'm camping or where I rent.
Hey I was wondering are we going to talk about the video up today or go on and on about a muffler which has nothing to do with todsy. Hey why don’t you go thru the list of videos that have nothing to do w this video get all your links at the bottom im gonna keep searching for a video about reducing sound on my generator only and I’ll pass back in 20 min or so to see if your finished listening to you voice and watching uourself on tv. Thanks for the muffler tips im positive I’ll never think about it again. If I go to your muffler video you think your generator info is there bc it’s not here
From my engineering classes, -3 dB cuts the sound in half. So a 9 dB reduction is about 1/8th. The formula for 10 dB would be 1÷(2^(10/3)) = 0.099 or 1/10th. So you made a huge improvement.
Man, this is awesome!
Truly! It's simple, it's cheap and it's effective!
Bravo, sir!! BRAVO!!!
Dude, im gonna try this. Mine is loud
Very interesting video..thanks for sharing. From my experience, the only Robin / Subaru small engine that I've seen quit running were ones that were severely neglected. I saw one that was run with no oil till it knocked, then they put oil in it and it ran for a long time afterwards, knocking away for about a year. That was on a gas air compressor!
D. J. Tanner This one double failed. The oil level sensor that is supposed to shut off the engine when the oil is low, died and would not allow the engine to start. So the original owner pulled the kill wire to this sensor so it could be run. He sold it to a guy(never told him this was unplugged) who figured it had the low oil shut down so he never needed to check the oil.... wham bam bang, there's no longer a piston rod and she's mine now.
D. J. Tanner I am a believer in Subaru products. They have proven themselves over and over again.I have a 1995 wagon with over 500.000 miles and still going strong.
*****, I love anything Subaru. Our first Subaru when I was 10 years old, was a 1979 GL 1600 4wd Wagon. It's was tough, dependable and so fuel efficient and went like a tank in snow. Subaru customer loyalty is amazing! My fiancé will only drive Subaru vehicles.
D. J. Tanner I've seen quite a few of them die for no reason,and have gotten some great deals due to their failures..I would not buy anything with one of them on it unless the deal was practically a gimme,or good enough to compensate for the new engine that I am going to have to put into it before too long...
I've owned 3 Subaru 1 Nissan and 1 Toyota and 1 Honda, the Honda was the only one who blew the tranny. I'm not saying hondas are bad but Subarus make excellent products.
Doesn't that restrict airflow and cause motor to run at a higher temperature which will shorten the life of the unit?
Still good enough airflow. It doesn't need a Crazy amount
Yea, I'd think creating a hot box isn't good.
As a mechanic this is not advisable . Generation units are designed at there max to preform . Restricted airflow with a cover will heat the engine and gen set. My advise keep a good factor high flow muffler on it and use a good cord that's heavy and long lol
@@ronaldbrown5991 here's a simple analogy. If you're cold at night time you put a blanket over you, if you're hot you remove the blanket. Enough said?
@@Hicaliber1 I guess you could put it like that
I do a similar thing, temporarily, for my General. But also have built another version which provides about 3-ft spacing for fire protection and ability to redirect the sound into a particular direction into the dense forest. But this still leads to poor airflow for cooling. Even at -8F, the sound box will heat up to the 70’s, imagine when it is +80F.
We live off grid and do what we can to use the gens the least and the quietest. We will be enlargening the sound box and adding studio egg crate foam, hopefully before the winter.
In the army we used to just prop a six foot table on its side by the generator, it sure made a difference.
10dB reduction is percieved as halv the sound.
@@ctrlaltdel138 i know my decibels, and 10 decibel is not a factor of hundred ;)
It appears to be deflecting the sound into the ground, I would like to see how this works on solid ground or a wooden floor.
yep, on concrete or macadam , like a garage or driveway....
I hope you’re not planning to use one on an interior wood floor for hopefully obvious reasons.
you are a scientist, an engineer
Wow!!! Its simple and it looks beautiful in your garden or patio.
I built a 1 end, and one side box with a floor and hinged top out of plywood. So one open end and one open side. The top, side and end were lined with 1 1/2" styrofoam insulation. The exhaust side was facing the open side of box. The open end made it possible to roll the generator into the box. The hinged top made it possible to refuel easily. This was for my camp with a 5000w gen. The exhaust side faced the woods behind the camp. Worked well.
Awesome.